A tool holder for a machine tool, in particular for a core drilling machine, having a hollow shaft which has, at one end for coupling to the drive of the machine tool, a connector and, at the other end, a receiving opening with a plurality of openings in which locking elements are accommodated which are radially adjustable between a clamping position and an release position for securing a tool accommodated in the receiving opening. A switching sleeve is provided, which is adjustably mounted on the hollow shaft between a first switching position and a second switching position, a first subset of the locking elements being provided in the first switching position for locking the tool in the receiving opening, and a second subset of the locking elements being provided in the second switching position for locking the tool in the receiving opening, while the adjustment of the respective remaining locking elements is deactivated.

A tool holder for a machine tool, in particular for a core drilling machine, having a hollow shaft which has, at one end for coupling to the drive of the machine tool, a connector and, at the other end, a receiving opening with a plurality of openings in which locking elements are accommodated which are radially adjustable between a clamping position and an release position for securing a tool accommodated in the receiving opening. A switching sleeve is provided, which is adjustably mounted on the hollow shaft between a first switching position and a second switching position, a first subset of the locking elements being provided in the first switching position for locking the tool in the receiving opening, and a second subset of the locking elements being provided in the second switching position for locking the tool in the receiving opening, while the adjustment of the respective remaining locking elements is deactivated.

A facing head as well as a method for inserting a tool into and/or removing a tool from a tool holder device of the facing head. The facing head has a spindle coupling device for exchangeably coupling with a spindle chuck of a working spindle of a machine tool. The facing head has a housing body at which or in which a facing slide is moveably supported in a guided manner. The facing slide supports the tool holder device. The tool holder device is hydraulically controllable. A hydraulic coupling that is mechanically and hydraulically coupled with an associated hydraulic control coupling of the housing body in a tool change position of the facing slide. Remote from the tool change position, the mechanical and hydraulic connection between the hydraulic coupling and the associated hydraulic control coupling is interrupted. In the tool change position a switching of the tool holder device between a hold condition holding the tool and a release condition releasing the tool can be carried out by a respective pressurization with hydraulic pressure.

Portable milling machine having a housing, a spindle and a clamping nut, which, as part of a tool holder, can be rotatably connected to the spindle and detached therefrom in order to clamp and unclamp a milling tool, and the portable milling machine having a spanner, which can be moved relative to the spindle axially between an engaged position and a disengaged position, the spanner interlockingly surrounding the clamping nut at least in portions in the circumferential direction in the engaged position and, when the spanner is in the disengaged position, the clamping nut being rotatable relative to the spanner, the spanner being connected to the housing of the portable milling machine for conjoint rotation such that, when the spanner is in the engaged position, the clamping nut can be connected to the spindle and detached therefrom by manually rotating the spindle.

Portable milling machine having a housing, a spindle and a clamping nut, which, as part of a tool holder, can be rotatably connected to the spindle and detached therefrom in order to clamp and unclamp a milling tool, and the portable milling machine having a spanner, which can be moved relative to the spindle axially between an engaged position and a disengaged position, the spanner interlockingly surrounding the clamping nut at least in portions in the circumferential direction in the engaged position and, when the spanner is in the disengaged position, the clamping nut being rotatable relative to the spanner, the spanner being connected to the housing of the portable milling machine for conjoint rotation such that, when the spanner is in the engaged position, the clamping nut can be connected to the spindle and detached therefrom by manually rotating the spindle.

A method for holding a spindle of a mobile power tool in order to allow an opening and/or a closing of a tool fitting by turning an operating part of the tool fitting relative to the spindle, where the spindle is rotationally coupled to an electric motor. The method includes detecting a rotation of the spindle and/or of the electric motor in a first direction while a setpoint angular velocity is zero and controlling the electric motor to generate a torque in a second direction which is opposite to the first direction.

A workholding apparatus (10) wherein a draw bar (22) effects chucking and de-chucking of a workpiece (W) and wherein un-seating of the workholding apparatus is effected by piston-like mechanisms (30) located in a machine spindle (2).

A workholding apparatus (10) wherein a draw bar (22) effects chucking and de-chucking of a workpiece (W) and wherein un-seating of the workholding apparatus is effected by piston-like mechanisms (30) located in a machine spindle (2).

The invention relates to a modular tool comprising a body and an insert for machining a workpiece, wherein the insert comprises a tenon for insertion into a receptacle of the body, wherein the body comprises an access hole, through which the tenon is accessible for an assembly tool, wherein the tenon comprises a profile portion, which, upon insertion of the assembly tool into the access hole, engages with a lateral surface of the assembly tool so that, by a rotation of the assembly tool, the insert can be ejected from the receptacle. Furthermore, a method for ejecting an insert of such a modular tool is specified.

A tool bit holder for connecting a rotary tool to a rotary tool driver. The tool bit holder including a body having a driver end configured to connect to a rotary tool driver and a tool end, a tool retainer bore, and a tool retainer movably received within the tool retainer bore and movable between an engaged position and a retracted position. The tool bit holder further includes an actuator sleeve, a sleeve spring for urging the actuator sleeve towards a first position, a plunger, and a plunger spring urging the plunger towards a loading position. A tool bit received in a tool receiving cavity pushes the plunger to a loaded position, and in the loading position the plunger extends over the tool retainer bore to engage the tool retainer and urge the tool retainer towards the retracted position.